Answer:
1 has the highest density because it has the most amount of circles in the least amount of space- it is the most densely filled with circles; it is the most dense.
Answer:
9.28
Explanation:
pOH refers to a measure of hydroxide ions concentration. pOH tells about the alkalinity of a solution. If pOH is less than 7 then aqueous solutions are alkaline, acidic if pOH is greater than 7 and neutral if pOH is equal to 7.
Concentration of the hydroxide ions = 1.9 x 10-5 M
pH = 
pOH = 14 - pH
=14 - 4.72 = 9.28
<span>An exothermic reaction is one in which heat is released from the reagents into the ambient environment. Perhaps somewhat counterintuitively, condensation is in fact an example of such a reaction. During the process of the gas-to-liquid phase change, water goes from a higher-energy to lower-energy state of matter, and, as such, releases heat into the environment.</span>
Answer:
See explanation
Explanation:
The oxides or hydrides are formed by exchange of valency between the two atoms involved. The group of the atom bonded to oxygen or hydrogen in the binary compound can be deduced by considering the subscript attached to the oxygen or hydrogen atom.
Now let us take the journey;
R2O3- refers to an oxide of a group 13 element, eg Al2O3
R2O - refers to an oxide of group a group 1 element e.gNa2O
RO2 - refers to an oxide of a group 14, 15 or 16 element such as CO2, NO2 or SO2
RH2 - refers to the hydride of a group 12 element Eg CaH2
R2O7 - refers to an oxide of a group 17 element E.g Cl2O7
RH3- refers to a hydride of a group 13 element E.g AlH3